Exterior of a truck cab



FIG. 1 is a right, front perspective view of an exterior of a truck cabshowing our new design, it may be understood that the broken lines arefor illustrative purposes only and form no part of the claimed design;

FIG. 2 is a back view thereof;

FIG. 3 is a right side view thereof;

FIG. 4 is a left side view thereof;

FIG. 5 is a front view thereof; and,

FIG. 6 is a top view thereof.

The ornamental design for an exterior of a truck cab, as shown anddescribed.